function youwin(tag,count){
    tag.parentNode.bgColor="";
    tag.src="Images/"+tag.name+".png";
    for(var i=0;i<game.place.height;i++)
        for(var j=0;j<game.place.width;j++)
            if(document.getElementById("area"+i+"_"+j).parentNode.bgColor=="black") count++;
    if(count==game.place.boomNum){stopcount();alert("你赢了!");}
    else {count=0;}
}